Final answer:
Chronic stress may contribute to the progression of diseases related to the immune system, but researchers are less certain about its influence on diseases not directly linked to immune response.
Step-by-step explanation:
Researchers are least likely to suggest that stress influences the progression of diseases in humans that have not been clearly linked with the immune response system. The fields of psychology, psychoneuroimmunology, and neuroscience have generated substantial evidence indicating that long-term or chronic stress can suppress immune system function, which leads to an increased risk of various health issues. Chronic stress has been associated with the progression of cardiovascular disorders, asthma, and possibly other psychological disorders such as major depressive disorder and post-traumatic stress disorder. However, it is less clear how stress might influence diseases not directly connected to the immune response.